JPS59142374A - Continuous melting electric furnace for cinder with continuous slag discharger - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for melting and processing urban sewage sludge, incineration residue of industrial waste, and chaff such as ash collected in a dust collector.

In general, much of the incinerated ash from municipal waste and the ash collected by dust collectors are disposed of in landfills. However, it is becoming increasingly difficult to secure landfill sites year by year, and there is a widespread demand for reducing the volume of rice husks.

On the other hand, in an effort to reduce the volume of municipal waste incineration ash, a so-called sump incineration ash melting furnace has been developed. However, various technical problems remain in existing waste incineration ash melting furnaces, and stable operation has not yet been achieved. For example, clinker may be generated at the molten ash removal port, making it impossible to take out the molten ash continuously, or it may be extremely difficult to continuously and completely melt the incinerated ash, making it impossible to reduce the volume sufficiently. The problem is that there is no.

The present invention basically solves the above-mentioned problems in the conventional waste-melting furnace, and aims to use a submerged arc furnace for melting chaff.

Therefore, electric melting furnaces are generally widely used in technical fields such as steel manufacturing, and are technically stable equipment. However, operating the furnace requires highly skilled and sophisticated operating techniques, and if it is incorporated into a garbage processing plant that melts and processes rice husks, many problems may occur.

First of all, in conventional electric melting furnaces, molten slag was extracted using an intermittent tap method, in which tap holes provided in the side walls of the pre-swaged furnace were opened to extract the slag, or by tilting the entire electric furnace. A tilting system is used in which the slag is discharged from a drain at the top of the furnace.

However, in the former intermittent tap method, it is necessary to periodically puncture the tap hole and plug it after tapping the slag, which requires skill and is dangerous, and the work environment is extremely poor. There is a problem.

Furthermore, even in the latter tilting method, when tilting, it is necessary to roll up the electrode to interrupt the load and also to interrupt the input of raw materials, resulting in extremely low processing efficiency.

The second problem is the sedimentation of molten metal in the hearth part 2 when husks containing a large amount of metals, such as incineration ash, are melted. In other words, since the specific gravity of metal is heavier than that of slag,
It settles to the bottom of the furnace. However, since the depth of the molten material is generally constant, during long-term operation, the molten metal layer gradually becomes deeper, and conversely, the molten slag layer becomes shallower.

On the other hand, since the electrode is immersed in the molten slag layer, as the molten metal layer becomes deeper, the immersion depth of the electrode becomes shallower, resulting in a decrease in power load and a gradual decrease in melting capacity. .

In order to avoid a gradual decrease in melting capacity and always maintain a highly efficient melting state, it is necessary to periodically discharge the metal, keep the depth of the slag melting layer above a constant value, and adjust the immersion depth of the electrode. It is necessary to maintain it in the most efficient condition. By the way, the first possible method for discharging the molten metal is to open a tap hole provided at the bottom of the furnace. However, as mentioned above, this method has the drawbacks that the drilling operation requires special skill, the operation is dangerous, and the working environment is extremely poor.

On the other hand, even in the case of the tilting method, which does not require tap drilling, the conventional tilting type melting electric furnace sets either raise the electrode to the outside of the furnace and tilt the furnace body, or integrate the furnace body and the electrode device. The entire device is tilted. However, in the former case, it is necessary to interrupt the load while the electrode is being pulled up, and if a furnace lid is provided, the electrode must be completely pulled up to the top of the furnace lid, resulting in a long electrode lifting distance. However, the disadvantage is that the electrode equipment itself becomes larger. In the latter case as well, there is a drawback that the entire equipment including the electrode device is tilted, resulting in significant damage to the tilting device.

The third problem is the problem of inputting raw materials such as rice hulls.

In conventional electric melting furnaces, a so-called batch method is often used for melting. However, batch-based melting processing has a certain limit in melting efficiency, making it unsuitable for melting rice husks and the like. In other words, in order to achieve stable continuous melting and continuous slag extraction and to improve processing efficiency, it is necessary to efficiently and continuously feed the raw material (rice husks) into the furnace. In order to maximize the melting efficiency, it is necessary to charge the material uniformly between the electrodes from the respective charging chutes in a way that adapts to the melting speed.

The present invention aims to solve the above-mentioned problems when treating rice husks from urban areas, etc. using an electric melting furnace.・Continuous melting and continuous slag extraction are possible, the melting efficiency is extremely high, and ・Moreover, the device is compact and has a continuous slag extraction device that enables a significant reduction in equipment and operating costs. The purpose is to provide a continuous melting electric furnace.

In other words, the first invention of the present application makes it possible to significantly improve the melting efficiency of the furnace by omitting the dangerous tapping work that requires extremely high skill level, and by enabling continuous melting and continuous slag tapping. The present invention provides an electric furnace for continuous melting of Toshidamoe husk.

Further, the second invention of the present application makes it possible to discharge only the molten metal without causing any damage by making it possible to tilt only the furnace body without increasing the size and complexity of the equipment and without pulling the electrodes out of the furnace. To provide an electric furnace for continuously melting chaff, which can maintain a highly efficient molten state.

Furthermore, the third invention of the present application makes it possible to achieve high melting efficiency, stable continuous melting, and continuous slag production by supplying rice husks into the furnace extremely uniformly and in accordance with the melting rate in the furnace. The present invention provides an electric furnace for continuous melting of roasted rice hulls.

In order to achieve the above-mentioned problems, in the first invention of the present application,
In an electric furnace for melting rice husks (A) of Tomi Tomi, etc., an overflow weir (8
) and an unmelted matter obstruction plate (9) arranged in the form of a hanging wall from above inside the furnace. Located on or near the line connecting any electrode 0 pier and core (0) [However, P
- electric furnace load (W), constant of K-16 to 25].

Further, the second invention of the present application is an electric furnace for melting rice husks (A) of urban tomi, etc., which includes an overflow weir (8) of an appropriate height on the side wall of the furnace body (1) and the furnace. A slag outlet (
7), and connect the slag outlet (7) to the line connecting any electrode o in the reactor body (1) to the reactor core (0) or its (C
m) (where P - electric furnace load (W), K = constant between 16 and 25), and the furnace body (1) is set to a tilting device (21
) is supported so as to be tiltable toward the slag outlet (7) side,
The basic configuration is that a cylindrical heat-resistant flexible plate (3) is interposed above the furnace body (1) and a furnace lid (2) is attached.Furthermore, the third invention of the present application includes: In an electric furnace for melting rice husks (A) of urban Tomi etc., on the side wall of the furnace body (1),
A slag opening (7) consisting of an overflow weir (8) of an appropriate height and an unmelted matter obstruction plate (9) arranged in the form of a wall hanging from above on the inside of the furnace is formed, and the slag opening (7) on or along the line connecting any electrode (6) in the reactor body (1) and the reactor core (0).
cm) (However, P - electric furnace load (W), K = 16-2
5], and a temperature detector (2) for the in-furnace gas (27) above the furnace, and a light intensity detector for the melt (5) in the middle of the flow path of the outflowing melt (5). (26) are respectively arranged, and the detected values of the temperature detector (20) and the light amount detector (26) are compared with the respective input condition setting values, and when both conditions are satisfied, the input control device (25a) controls the raw material The basic configuration is to open the charging gate α0 and charge a predetermined amount of rice husks (A) into the furnace.

EMBODIMENT OF THE INVENTION Hereinafter, the details will be explained based on one embodiment of the present invention shown in the drawings.

FIG. 1 is a schematic vertical cross-sectional view of an electric furnace for continuously melting rice husks according to the present invention, and FIG. 2 is a cross-sectional view cut along the line a-a of FIG. 1. Further, FIG. 3 is a partially vertical schematic diagram showing a state in which the furnace body is tilted. In Figs. 1 to 3, 1 is the furnace body, 2 is the furnace lid, 3 is a cylindrical heat-resistant flexible plate that airtightly connects the furnace body 1 and the furnace lid 2, and 4 is the furnace bottom. 5 is a molten material (molten slag), 6 is an unmelted material, and 7 is a slag outlet provided on the side wall of the furnace body 1. The slag discharge lower is composed of an overflow weir 8 formed below the side wall of the furnace body 1, and an unmelted matter obstruction plate 9 formed in the shape of a wall hanging from above the furnace body 1 in front of the overflow weir 8. A drain 10 is provided below the overflow weir 8.

In each of the above figures, 11 is a drain cover made of heat insulating material, 12 is an electrode, 13 is a dust collection duct, 14 is an electrode lifting device, 15 is a raw material input chute, and 16 is a raw material input case 1.
-517 is a raw material hopper, 18 is a level detector, 19 is a hopper operator, 20 is a chaff distribution conveyor,
21 is a tilting device for the furnace body 1, 22 is a dust collector, 23 is an induced draft fan, 24 is a slag conveyor, 25 is a temperature detector, 26 is a light amount detector, 27 is a furnace gas, 28 is a support frame, 29 is a slag pit, and 30 is a heat-resistant flexible cylinder that connects the drain 10 and the pit 29 in an airtight manner.

The slag discharge lower is disposed on or near a line connecting any one of the three electrodes 12, 12, 12 and the furnace center (0), and the height of the overflow weir 8 is as follows: It is appropriately selected depending on the throughput of the electric melting furnace so as to obtain the most efficient pool depth. Further, the unmelted material obstruction plate 9 is placed approximately perpendicular to or in the vicinity of a straight line connecting one of the side electrodes 12 and the furnace center O, and its lower end position is slightly lower than the molten metal overflow weir 8. It is provided in a state where it is slightly immersed in the molten metal pool, and it dams up the outflow of unmelted material 6 and allows only the molten slag to pass through and overflow from the overflow weir 8 to the sink trough 10.

The overflow weir 8 needs to be installed at a position where it can always maintain a temperature at which the molten slag can easily overflow, and based on the flow characteristics of the molten chaff and various experimental results, The distance (L) between the flow weirs 8 has been determined. In other words, in conventional electric melting furnaces, furnace dimensions such as electrode diameter, distance between electrodes, and grate area, as well as load conditions such as current, voltage, and power density, vary depending on the properties of the melt. is adopted. However, in the case of melting rice husks (e.g. garbage incineration ash), the basicity (C and 0) is as low as 0.3-04, so the fluidity is extremely low.
tO2 is poor, and as a result, it is necessary to keep the molten metal temperature at 1500°C to 1700°C at all times in order to ensure good fluidity.

At the above-mentioned molten metal temperature, it may be 10 t/day to 60 t/day.
When continuously overflowing slag with a processing capacity of /day,
In order to ensure good fluidity at all times in the overflow part, it is necessary to arrange the overflow part within the melting zone formed by the energy supplied from the electrodes.

For this purpose, the outer surface of the electrode 12 is closest to the overflow weir 8, and by setting this distance, it has been demonstrated that the overflow part is always located within the melting zone and good fluidity can be ensured. has been done. However, in the previous equation, P is the electric furnace load (
w), K is a constant between 16 and 25, and the above equation was derived based on the results of a large number of melting tests.

The furnace main body 1 is supported by a support frame 28 and a tilting device 21.
The slag output lower side is supported so as to be movable in the vertical direction, and the slag output lower side is supported by the support shaft 28a by the operation of the cylinder 21a.
Moves up and down using the fulcrum as a fulcrum. A flexible pipe 13b is interposed in the dust collection duct 13a, and a cylindrical heat-resistant flexible plate 30 is provided to provide an airtight connection between the lower end of the drain 10 and the upper end of the slag pit 29. The furnace body 1 can be tilted smoothly.

On the other hand, the furnace cover 2 and the electrode 1 disposed thereon so as to be able to rise and fall freely.
2. The raw material input chute 15, the dust collection duct 13, etc. form the so-called fixed part of the electric melting furnace, and the space between the fixed part and the movable part of the furnace body 1 is kept airtight by a cylindrical heat-resistant flexible plate 3. connected in the same way.

A temperature detector 25 for detecting the gas temperature in the melting electric furnace is attached to the furnace M2, and a slag pit 29 is attached to the furnace M2.
A light amount detector 26 is provided above. The temperature detector 25 and the light amount detector 26 respectively control the charging of the rice husks A into the furnace.
A material charging control device is constituted by a charging control device 25a, a temperature setting device 25b, etc., which are operated by these signals.

That is, when the chill A is also put into the melting electric furnace, the temperature of the furnace gas 27 is temporarily lowered. Thereafter, as melting progresses and the amount of unmelted material 6 decreases, the temperature of the gas in the furnace rises in accordance with the decrease.

Therefore, there is a very strong correlation between the rise in gas temperature and the amount of unmelted material in the furnace, and as a result, the gas in the furnace 27
If the temperature of the unmelted material 6 in the furnace is detected by the temperature detector 25 and the decrease in the unmelted material 6 in the furnace is detected as an increase in the gas temperature, it is possible to know the progress of melting in the furnace. It is possible to detect the timing of input.

Moreover, the amount of slag of the melt 5 from the slag removal lower is increased by charging the rice husks A into the furnace. This is because the molten material 5 is pushed down by the weight pressure of the unmelted material 6, and the overflow area from the overflow weir 8 increases. Then, as the amount of unmelted material 6 decreases, the amount of slag gradually decreases.

In this way, there is an extremely strong correlation between the amount of unmelted material 6 and the amount of slag, and it is possible to know changes in the amount of unmelted material 6 in the furnace by detecting changes in the amount of slag. can. That is, if a change in the amount of light emitted by the flowing molten material 5 is detected by a photoelectric conversion element or a light amount detector 26 using industrial <Tv, a decrease in the unmelted material in the furnace can be detected as a decrease in the amount of hot water coming out. This can be prompted by a decrease in the amount of light, and from this it is possible to sense when it is time to add raw materials.

In the embodiment shown in Fig. 1, the timing of charging rice husks A into the furnace is controlled based on both the gas temperature in the furnace and the amount of light emitted by the slag, and both of them are based on the preset raw material charging conditions. The configuration is such that when the number 1 matches, the rice husks A are thrown in.

That is, a temperature corresponding to the limit value of increase in gas temperature in the furnace is set in the temperature setting device 25b, and a signal from the temperature setting device and an output signal from the temperature detector 25 are sent to the immersion control device 25.
a, the output of the temperature detector 25 is the temperature setter 25.
It is determined whether the output exceeds the output of b.

Similarly, the output signal of the light amount detector 26 is input to the control device 25.
a, and compares this input signal with a setting value set based on the minimum amount of slag output in advance to determine the charging condition. Then, when both the input conditions on the temperature detector 25 side and the input conditions on the light amount detector 26 side are satisfied, the input control device 25a causes the raw material input gate 16 to be opened for a certain period of time.
A command is issued, and a predetermined amount of new rice husk A is sent to the furnace for automatic transmission to humans.

Next, the effects of the present invention will be explained. Referring to FIG. 1, rice husks (A) are collected in a raw material hopper 17 by a distribution conveyor 20, and are fed into a melting electric furnace via a plurality of raw material input shoes (15) attached to a furnace lid 2. The raw material hopper 17 is provided with a level detector 18, a hopper entrance gate 19, and a raw material input gate 16, respectively.
The raw material input gate 16 is fully opened by a signal from the input control device 25a when raw materials are input into the furnace, and the entire amount of rice husks (A) in the raw material hopper 17 is input into the furnace. still,
The opening/closing timing of the raw material input gate 16 is when both the input conditions on the temperature detector 25 side and the input conditions on the light amount detector 26 side are satisfied, as described above.

The rice husks (A) uniformly charged between each electrode from the charging chute 15 are sequentially melted in the furnace, and as shown in Fig. 1, the rice husks (A) are melted in the furnace during steady operation. A molten metal 4 is formed on top of which a molten metal 5 and an unmelted metal 6 are layered.

When the depth of the molten material 5 exceeds a certain value, the weight pressure of the unmelted material 6 acts, so that it passes through the lower part of the unmelted material obstruction plate 9 slightly immersed in the molten pool and flows from the overflow weir 8 to 1. Naritsugu overflows and flows down the drain 10. Incidentally, since the melted material 5 is pushed upward through the overflow portion 5a by the weight pressure of the unmelted material 6 as described above, in reality, it overflows in proportion to the input amount of the rice husks (A).

On the other hand, when the charging of rice husks is stopped, the overflow of the melt 5 gradually decreases, and finally the overflow stops.

However, since the overflow portion 5a is located within the melting zone of the nearest electrode 12 as described above, the melt field near the overflow portion is maintained in its original state. Therefore, the rice husk again (A)
As soon as the melt 5 is added, the overflow of the melt 5 will be resumed.

As the melted material 5 overflows, there is a possibility that a portion of the unmelted material 6 moves toward the slag discharge lower side. However, since the obstruction plate 9 is provided in front of the overflow part 5a, the unmelted material 6 will not overflow together.

Further, the upper part of the overflow weir 8 and the upper part of the drain trough 10 are covered with a heat-retaining furnace material cover 11, so that the flowing slag is not cooled and solidified on the way.

In addition, the generated scum 27 in the furnace, the overflow part 5a, and the slag bit 2
The generated gas in the dust collection duct 13 and the branch duct 9)
13 a and is drawn out to the dust collector 22 . Six test conditions were used to conduct a melting test of waste incineration ash (dry ash) using an electric melting furnace with a capacity of 500 KVA.The electric furnace load was 300,000 W, and the electrode diameter was 20.3 cm.

The distance between the electrode surface and the overflow weir surface is 28.0 am. According to the results of this test, the consumption amount per 1 ton of incinerated ash is 5.
It was 60-850KWH. In addition, the melting capacity is 10t/
Extremely stable continuous melting and continuous slag tapping operations were possible on 7 days a week.

If the rice husk A contains a large amount of metals, molten metal 4 accumulates as the furnace operating time passes, and it is necessary to discharge this to the outside. When discharging, the electrode 12 is first pulled up to the extent that it does not hit the molten metal layer 4, and the tilting device 21 is activated to move the furnace body 1 around the support shaft 28a of the support frame 28 as shown in FIG. The molten metal 4 is discharged out of the furnace through the overflow part 5a.

At the beginning of the tilting of the furnace body 1, both the molten material 5 and the molten metal 40 pass together under the unmelted material obstruction plate 9, but from the middle stage of the tilting, the molten material 5 is blocked by the obstruction plate 9. , only the molten metal 4 passes through and is discharged to the outside.

If the furnace body 1 is returned to its original position when the molten metal 4 is almost discharged, the depth of the molten material 5 will not change much, so the melting will occur under almost the same load conditions as before the molten metal 4 was discharged. can be continued.

Even during tilting, the gap between the furnace body 1 and the furnace M2 is connected by the heat-resistant flexible plate 3, and the gas inside the furnace is drained through the dust collection duct l.
Since the suction is carried out through -13, there is no possibility that gas or dust will be scattered outside the furnace or that heat radiation will increase.

The input control for rice husks (A) is as described above, and the temperature setting device 25b is set to the temperature that corresponds directly to the rise limit of the gas temperature in the furnace, and the light intensity that corresponds to the limit value of the amount of slag produced is set in the temperature setting device 25b. The signal values are respectively set in the input control device 25a.Then, the output signal of the temperature detector 25 and the output signal of the light amount detector 26 are compared with the respective set values, and when both input conditions are respectively satisfied. Then, the input control device 25a issues a command to the raw material input game 16 to open for a certain period of time, and a predetermined amount of rice husks (A) is supplied.When the rice husks (A) are supplied, the weight of the rice husks (A) is Pressure increases melt overflow.

In this way, the rice husks (A) are continuously melted and dregs are produced.
Although the capillaries (A) are added when both the input conditions on the 5 side and the light amount detector 26 side are satisfied, it is also possible to use a control method that starts inputting according to some of the conditions. It is. As described above, the first invention of the present application forms a slag lower which is composed of an overflow weir 8 and an unmelted matter obstruction plate 9 on the side wall of the furnace main body 1, and also determines the formation position of the slag lower and the electrode 12 and the overflow weir 8. Since the distance (L) between them is regulated, the slag of the melt 5 can be continuously and smoothly discharged. the result,
The rice husks (A) can also be added continuously, and extremely high melting efficiency can be achieved.

In addition, the conventional tap hole drilling work is no longer necessary, and it is safe and does not require a skilled engineer with special skills.

Furthermore, regardless of whether slow cooling or water pulverization is adopted as the method for cooling and solidifying the slag, the amount of slag remains constant, so the capacity of the cooling and solidifying equipment can be small, reducing manufacturing costs. There are other benefits.

Next, the second invention of the present application regulates the formation position of the slag lower and the distance (L) between the electrode 12 and the overflow weir 8 as described above, and also connects the furnace body 1ξ and the furnace lid 2 to a cylindrical heat-resistant flexible They are connected by the plate 3, and only the furnace body 1 can be tilted by the tilting device 21. Therefore, by tilting only the furnace body 1 while the attached equipment of the melting electric furnace is fixed, the unmelted obstruction plate 9 can be tilted. Only the metal molten material 4 can be discharged extremely easily while the molten material 5 is dammed up.

In addition, the configuration of the device itself is simple and can be manufactured at low cost.
Even when it is returned to the horizontal state after tilting, there is almost no change in the depth of the melt 5, so it can be operated under substantially the same load condition as before tilting, and high melting efficiency can be achieved. Moreover, the tilting operation can be easily performed remotely and automatically, and has the advantage that it is safe and does not require a skilled technician.

Furthermore, the third invention of the present application is to form the slag lower on the side wall of the furnace main body 1, and to detect the state of the unmelted material 6 by detecting the gas temperature in the furnace, and to measure the amount of light of the slag. The unmelted material 6 and the amount of slag produced are detected, and a predetermined amount of new rice husks (A) is introduced when both the detection signals of the gas temperature and light amount are respectively just outside the setting 1. As a result, it is possible to efficiently and continuously feed rice husk (A) according to the melting state and slag state in the furnace, resulting in stable melting and slag production, and a significant improvement in overall processing efficiency. becomes possible.

As mentioned above, the present invention has excellent practical utility.

[Brief explanation of drawings]

FIG. 1 is a schematic vertical cross-sectional view of an electric furnace for continuously melting rice husks according to the present invention, and FIG. 2 is a schematic cross-sectional view taken along the line aa in FIG. 1. FIG. 3 is a partially vertical schematic diagram showing a state in which the furnace body is tilted. 1 Furnace main body 17 Raw material pumper 2 Furnace lid 18 Level detector 3 Cylindrical heat-resistant flexible plate 19 Hopper entrance gate 4 Melt metal
20 Distribution conveyor 5 Melt 2
1 Tilt device 6 Unmelted material 22 Dust collector 7 Slag outlet 23 Induced draft fan 8 Overflow weir 24 Slag discharge conveyor 9 Unmelted material obstruction plate 25 Temperature detector 10 Sink gutter
25a Official control device 11 Sink gutter cover 2
6 Light amount detector 12 Electrode 27
Furnace gas 13 Dust collection tact 28 Support frame 14 Electrode lifting device 29 Slag pit 15
Raw material input chute 30 Heat-resistant flexible cylindrical body 16 Raw material input game 1-A Moehara Patent Applicant Takuma Research Institute Co., Ltd. Continued from page 1 0 Inventor Mihara Jobu 9-3 Motomachi Fushiki, Takaoka City 0 Invention Person: Kiyoaki Takai 1-22, Fushikiyata Kamimachi, Takaoka City 0 Applicant: Japan Heavy Chemical Industries, Ltd. 8-4, Nihonbashi Koamicho, Chuo-ku, Tokyo

Claims (1)

[Scope of Claims] 1. In an electric furnace for melting rice husks (A) such as municipal waste, an overflow weir (8) of an appropriate height and an overflow weir (8) of an appropriate height are provided on the side wall of the furnace body (1) and the inside of the furnace. forming a slag outlet (7) consisting of an unmelted matter obstruction plate (9) arranged in the form of a hanging wall from above;
Connect the slag outlet (7) to any electrode C12 in the furnace body (1).
An electric furnace for continuous melting of rice husk, characterized in that the continuous slag extraction device is located on or near a line connecting the reactor core (0) and the electrode 0 is set to a constant between -16 and 25. . 2. In an electric furnace for melting rice husks (A) of urban trees, etc., an overflow weir (8) of an appropriate height is installed on the side wall of the furnace body (1), and a wall-shaped wall hanging from above is installed on the inside of the furnace. A slag outlet (7) is formed with an unmelted material obstruction plate (9) arranged at The furnace body (1) is positioned on or near the line connecting the electrodes, and the electrode α is set to a constant of -16 to 25], and the furnace body (1) is moved to the slag outlet (7) by a tilting device (21).
) side, and a furnace lid (2) is attached to the furnace body (1) with a cylindrical heat-resistant flexible plate (3) interposed above the furnace body (1). Electric furnace for continuous melting of rice husk with equipment. 3. In an electric furnace for melting rice husks (A) of urban trees, etc., an overflow weir (8) of an appropriate height is installed on the side wall of the furnace body (1), and a wall-shaped wall hanging from above is installed on the inside of the furnace. A slag outlet (7) is formed with an unmelted material obstruction plate (9) disposed in the reactor body (1) and the reactor core ( 0), and the distance (L) between the outer surface of the electrode (2) and the outer surface of the overflow weir (8) is L = 1.6 x a constant of -16 to 25]
A temperature detector (251) for the furnace gas (27) is installed in the upper part of the furnace, and a light intensity detector (26) is installed in the middle of the flow path of the outflowing melt (5). Detector (2
5) When each detection value of the light amount detector (26) is outside the set value, the material input gate α is opened by the input control device (25a), and a predetermined amount of rice husks (A) is introduced into the furnace. An electric furnace for continuously melting rice husks, which has a continuous slag device.